Recently, as performance of a general purpose computer has been developed and a processing capability of mobile terminals has been improved, power consumption for processing multi-media data through mobile terminals has been keep increased. Regarding playing multi-media files, image/video processing techniques have been developed. In particular, video CODEC called as “MPEG or H.264” has been widely adopted due to its high image/video quality and high compression rate.
However, the image/video processing techniques require large amount of internal arithmetic operations and, thus, a high capacity memory is needed. Meanwhile, MPEG/H.264 technique for mobile devices, performance is restricted by battery life, and, thus, using the low supply voltage is widely used in order to reduce power consumption in an integrated circuit.
During a MPEG/H.264 arithmetic operation, when a supply voltage is decreased, malfunctioning in the data path can be prevented by reducing an operating frequency. However, as for a memory device for storing data for MPEG/H.264 arithmetic operations, a failure cannot be prevented by reducing an operating frequency.
Failure in reading and writing cells inside the embedded memory for image/video processor can be occurred when variation in process condition or a voltage or a temperature happens. If such a failure affects an output data, deterioration in image quality of a video may occur.
In order to minimize such deterioration in image/video quality in low supply voltage operation, a method of using eight or ten transistors instead of six transistors for 1 bit memory cell has been proposed. Also, a method of correcting errors in images/videos by using an error correction code has been suggested. These methods enable the embedded memory to be operated with a lower voltage but require a large circuit area or additional design costs.
Thus, a low cost technique is needed in order to prevent video quality from being deteriorated by the failure of the embedded memory even if an image/video processing circuit is operated with low operating frequency. Therefore, the present disclosure suggests an embedded memory design optimized for an image/video processing digital signal processing circuit.